The way the federal government analyzes intense rain events isn’t keeping up with the reality of climate change, and that has serious implications for infrastructure projects and the availability of, and rising cost of, flood insurance.
Severe rainstorms, sometimes described as “atmospheric rivers” or “torrential thunderstorms,” are making the concept of a “1-in-100-year flood event” obsolete, according to a report from First Street Foundation, an organization focused on weather risk research.
These events are occurring more frequently due to the impact of climate change, but federal rainfall analysis, managed by the National Oceanic and Atmospheric Administration, isn’t keeping up with the new weather conditions, First Street says.
Half the people in the U.S. live in a county where a 1-in-100-year flood is at least twice as likely now as it had been in the past, coming once every 50 years instead of every 100 years. In some areas, a so-called “1-in-100-year” rainfall could now happen far more frequently—as often as every 5 to 10 years.
The outdated analysis has serious implications for the way infrastructure projects are initiated and designed. And, because FEMA’s federal flood insurance program greatly underrepresents the number of people that could fall into FEMA’s Special Flood Hazard Areas, millions of Americans may be unaware of their current flood risk.
Inaccurate flood risk data due to underestimating the impact of rainfall also impacts the cost and availability of flood insurance—this is especially true for property that isn’t close to the ocean or inland bodies of water.
The government is working to remedy the situation, though. NOAA, as reported by CNN, says it is working on a revamped approach to its rainfall analysis that is expected to be completed in 2027.
Related Stories
Codes and Standards | Oct 26, 2021
Dept. of Energy’s REScheck tool updated for the 2021 International Energy Conservation Code
Previous version incorporated 2018 code.
Codes and Standards | Oct 20, 2021
New York City passes overhaul of construction codes
Over 600 major changes along with thousands of smaller updates slated for 2022.
Codes and Standards | Oct 20, 2021
One-quarter of U.S. critical infrastructure at risk of failure due to flooding
Police and fire stations, hospitals, airports, and wastewater treatment facilities face threat.
Codes and Standards | Oct 19, 2021
Pittsburgh enacts first-in-the-nation “Dark Sky Lighting” law
Applies to all city parks, facilities, and streetlights.
Codes and Standards | Oct 15, 2021
New Calif. law mandates use of lead-free plumbing fixtures
Must meet NSF/ANSI/CAN 61-2020 in 2023.
Codes and Standards | Oct 14, 2021
Building industry leaders urge governments to boost emissions reductions targets
Scores of large AEC firms and organizations sign letter to UN’s COP 26 group.
Codes and Standards | Oct 13, 2021
FEMA’s new flood insurance plan will sharply raise insurance costs for seaside properties
Risk Rating 2.0 will have more accurate assessment of flood risk.
Codes and Standards | Oct 12, 2021
Three new laws expected to spur more affordable housing in California
Trio of measures could aid carbon reduction in built environment.
Codes and Standards | Oct 11, 2021
New program to promote mass timber construction launched in Boston
City’s planning and development agency to award grants for projects in early-stage planning.
Codes and Standards | Oct 6, 2021
Intl. Code Council publishes EV and building codes resource
Assists communities in setting policies for electric vehicle charging requirements.
